/*
 * Copyright (c) 2022 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
import { BaseMatcher } from '../BaseMatcher.js';
import { IsNot } from './IsNot.js';
/**
 * Is the value null?
 */
export class IsNull extends BaseMatcher {
    matches(o) {
        return o == null;
    }
    describeTo(description) {
        description.appendText("null");
    }
    /**
     * Creates a matcher that matches if examined object is <code>null</code>.
     * For example:
     * <pre>assertThat(cheese, is(nullValue())</pre>
     *
     * @return The matcher.
     */
    static nullValue() {
        return new IsNull();
    }
    /**
     * A shortcut to the frequently used <code>not(nullValue())</code>.
     * For example:
     * <pre>assertThat(cheese, is(notNullValue()))</pre>
     * instead of:
     * <pre>assertThat(cheese, is(not(nullValue())))</pre>
     *
     * @return The matcher.
     */
    static notNullValue() {
        return IsNot.not(IsNull.nullValue());
    }
}
